Please compare between CFX 5.5 and CFX 4.4. If i need to solve industrial problems about CFD. Please suggest me to buy CFX Product.

CFX-4.4:structured multiblock mesh approach, segregated solvers (inc. AMG), vast quantity of open routines for the user to code extra models, conditions etc. large amount of physical and chemical model.

CFX-5.5: unstructured/structured, fully coupled solver, expression language, fortran routine coming in now and most CFX-4 models being transfered in the code. Very robust I find.

CFX-4 is still very much used by people doing chemical process and multiphase flows, one of the areas in which CFX excels compare to competition, but CFX-5 is catching up. As far as I have understood this will be the case in the next release due next May/June... CFX-5 has taken over completely in mechanical, automotive and aero applications in general. But check on their web site www.cfx.aeat.com

Just to add to the other poster's comments. While CFX-5 is catching up to CFX-4 in terms of the number of models, probably the biggest gap is Radiation modelling. You can't do discrete ordinates or Monte Carlo radiation modelling in CFX-5 yet. The May/June release that the other poster mentions includes many new multiphase features including free surface heat transfer and surface tention, MFR and GGI with multiphase, and others...

CFX-5 also has many features that CFX-4 does not have. It can run structured and unstructured grids, has mesh adaptation, has far better scalable parallelisation, a more flexible post processor, modern programmable command language (uses PERL!), expression language that eliminates the need for user fortran in many cases, much more flexible additional variable/scalar implementation... etc...

Neale